Devices and methods for treatment of abdominal aortic aneurysm

Abstract

Devices and methods for treating aneurysms, such as abdominal aortic aneurysms (“AAA”) generally include one or more stent-graft devices. Some embodiments include self-expanding and/or balloon-expandable stent components and one or more graft components coupled with the stent components. Using various combinations of self-expanding stent members, balloon-expandable stent members, graft members, and/or anchoring members enhances the anchoring abilities of a stent-graft device to prevent leakage around it, and may further allow the device to be adjusted after placement at a site for treatment. Some embodiments further include a skirt graft member for further prevention of leakage and/or device slippage.

What is claimed is: 
     
       1. A stent for implanting in a vessel, said stent comprising:
 an expandable stent having a first end, a second end opposite the first end and a central lumen extending therebetween, wherein the expandable stent has a collapsed configuration and an expanded configuration, and 
 wherein in the collapsed configuration the stent is configured for delivery to the vessel, and 
 wherein in the expanded configuration the stent is configured to engage the vessel, and 
 wherein in the expanded configuration a helical portion of the stent is disposed between the first and second ends, the central lumen in the helical portion having a helical configuration, and 
 wherein the helical portion is configured to direct blood flow through the central lumen so as to be sufficiently laminar to avoid causing an atherosclerotic response in the vessel due to turbulence or shear in the blood flow. 
 
     
     
       2. The stent of  claim 1 , wherein the stent is balloon expandable. 
     
     
       3. The stent of  claim 2 , wherein the stent comprises stainless steel. 
     
     
       4. The stent of  claim 1 , wherein the stent is self-expanding. 
     
     
       5. The stent of  claim 4 , wherein the stent comprises nitinol. 
     
     
       6. The stent of  claim 1 , wherein the stent comprises a balloon expandable stent member and a self-expanding stent member. 
     
     
       7. The stent of  claim 1 , wherein in the collapsed configuration, the stent is in a straight configuration. 
     
     
       8. The stent of  claim 1 , further comprising a tubular graft member coupled with the expandable stent. 
     
     
       9. The stent of  claim 1 , wherein the helical portion of the expandable stent disposed between the first and second ends has a sinusoidal shape. 
     
     
       10. The stent of  claim 1 , wherein in the expanded configuration the stent is configured to engage the vessel thereby preventing leakage therearound. 
     
     
       11. The stent of  claim 1 , wherein the vessel is an artery. 
     
     
       12. The stent of  claim 1 , wherein the stent comprises a series of diamond shaped sections. 
     
     
       13. The stent of  claim 1 , wherein the stent comprises a wire wound in a helical fashion. 
     
     
       14. The stent of  claim 1 , wherein the helical portion provides 360 degrees of helix. 
     
     
       15. The stent of  claim 1 , wherein the helical portion provides 540 degrees of helix. 
     
     
       16. The stent of  claim 1 , wherein the helical portion provides greater than 540 degrees of helix. 
     
     
       17. The stent of  claim 1 , wherein the stent is preformed with the helical portion. 
     
     
       18. The stent of  claim 1 , wherein the stent is configured for implantation in an aorta. 
     
     
       19. The stent of  claim 1 , wherein the stent comprises a first leg and a second leg, the first and second legs disposed between the first and second ends. 
     
     
       20. The stent of  claim 19  wherein one or more of the first leg and the second leg comprises the helical portion. 
     
     
       21. The stent of  claim 19  wherein the first leg comprises a first helical portion and the second leg comprises a second helical portion. 
     
     
       22. The stent of  claim 19  wherein each of the first leg and the second leg has a distal end configured for placement in an iliac artery. 
     
     
       23. The stent of  claim 19  wherein the first leg is helically entwined with the second leg. 
     
     
       24. A method for implanting a stent in a vessel, said method comprising:
 delivering an expandable stent in a collapsed configuration to a treatment region in the vessel, the stent having a longitudinal axis, a first end, a second end opposite the first end and a central lumen extending therebetween, the central lumen being formed around the longitudinal axis; 
 expanding the stent from the collapsed configuration to an expanded configuration in which the stent engages the vessel, and wherein expanding the stent comprises forming a helical portion of the stent disposed between the first and second ends, wherein the longitudinal axis in the helical portion has a helical configuration; and 
 permitting blood flow through the central lumen, wherein the helical portion creates sufficiently laminar blood flow so as to avoid causing an atherosclerotic response in the vessel due to turbulence or shear in the blood flow. 
 
     
     
       25. The method of  claim 24 , wherein expanding the stent comprises expanding the stent with a balloon. 
     
     
       26. The method of  claim 24 , wherein expanding the stent comprises allowing the stent to self-expand. 
     
     
       27. The method of  claim 24 , wherein expanding the stent comprises releasing the stent from a sheath or constraining device, thereby allowing the stent to self-expand. 
     
     
       28. The method of  claim 24 , wherein delivering the stent in the collapsed configuration comprises maintaining the stent in a straight configuration. 
     
     
       29. The method of  claim 24 , wherein providing the expandable stent further comprises providing a tubular graft member coupled with the expandable stent. 
     
     
       30. The method of  claim 24 , wherein expanding the stent to engage the vessel prevents leakage therearound. 
     
     
       31. The method of  claim 24 , wherein the vessel comprises an artery. 
     
     
       32. The method of  claim 31  wherein the artery comprises an aorta. 
     
     
       33. The method of  claim 32  wherein the stent comprises a stent graft and the method further comprises placing the stent graft across an aortic aneurism. 
     
     
       34. The method of  claim 31  wherein the stent comprises a first leg and a second leg. 
     
     
       35. The method of  claim 34  wherein the first leg is helically entwined with the second leg. 
     
     
       36. The method of  claim 34 , further comprising deploying a distal end of the first leg in a first iliac artery and a distal end of the second leg in a second iliac artery. 
     
     
       37. The method of  claim 24 , wherein the central lumen has a helical configuration in the helical portion of the stent.